Steering linkage



H. O. FUCHS Jan. 9, 1940.

STEERING LINKAGE Filed April 11, 1958 Snventor fizzqy 0 (7110125 lvg . (Ittornegs Patented Jan. 9, I

1 STE RINGLIN AGE Applieatien- April En. 1938 emi "No. 201,218-

it-clai (c1. ato -9'5) This. invention 1-. relates-std the steering; linkage and the dirigi'ble f between the steering gear vlheelsiofavehi It relates especially to asteering linkage for a pair ofiwheelsindependently suspended on oppositesides-oiaa motorvehicle frame, and capable of-dirigible movement in relation: to-the;s'dspen sion means. 7

i The steering linkage for Wheels thussu'sp'enw ed commonly includes a pair: o-fequalllen gth tie rodsco'nnec'ting steering arms associated with the wheel spindles to a lever armcentrally sit uated on the vehicle iramalwith'a reach-rod connecting'the leverarmtto asteeringi-gear towatdsz one side of thevehicle frame. Y

The object of the inventicnis to. eile Qt'BCOHOmY and simplification' cf the partsof asteeringlink;

age between independently. suspended 'di'rig'ib-le wheels anda steering ge'anwith a construction I such that the steering will be substantially urr-f afiected by upward anddownwarddeflections of the wheels relatively to the vehicle frame.

1 A further object of the invention is a construe-i tion in which the pivotal connections between crossing or overlapping links ,to interfere with each other. r

The above and other objects of the invention will be apparent as the description proceedsj According to the inventionjthe steering. linkon opposite sides of the vehicle and their other ends connected together by a ball j'ointj the pitman arm of the steering gear box mounted towards one side i of the vehicle frame; is 'ball jointed directly'to the tie rod at thatside' of the vehicle, at a point intermediate of its ends.

In the drawing" g S Fig. 1 is a plan view of the front end of a motor vehicle chassis having a steering linkage accord-,- ing to the invention. 1 'Y Fig. 2 is an enlarged elevational .viewof a part of Fig. 1. I

Fig. 3 is an enlarged other part of Fig. 1. i i

The framezside members land 2 are connected by a cross .member 3 at the front end of the vehicle. A well known type of independent suspension supports the frame on the dirigible". road wheeled and 5.- It consists, for each wheel, f ofshort upper and longer lower arms 6 and 'l re-z has a balljoint connection 20 with the tie at'a pcintintermediateof its ends.

. I I v I ried by the pitman arm I9. elevational View of anspectively, pivotally connectedz to the vehicle I I frame and-to the Wheelknuckle support, icr piv eta-l swinging inovementin a substantially Vera tica l transverse plane, with suitable means such j as the coilspring-8' resilientl resisting such jin'ovenient upward relatively to the frame. 1 The upper arms i'--V,:- haped in plan-have their spaced apartlimhs keyedor otherwise suite ably fixed to the actuatingspindlesof shock ab s'orbers 9 rigidly mounted on the cross members .The pivot axes of the arms .6 and 'lfii'orca'ch wheel"- are, as shown-, forwardlyzdivergent away from-the normallypvertical longitudinal midplane of'the vehicle. 4

-, A rearwardlyprojecting steeringarrn IQ is as it he.

getherby two tie rods l2 and i3, arranged end to .fend, with. a ball joint M at their juncture, and with ball joint connections [5 and it. to the steering arms.

. The steering column assembly, including the.

the tie rods and the steering gear are towards one gear box l8 mounted on the frame side member side of the vehicle frame, to avoid interference with the engine or other necessary parts mounted centrally between the wheels, and'without any l, is ofiset from the longitudinal center line of' the vehicle, and actuates a pitrnan arm l!) which rod I2,

As shown most clearlyin Fig. 3, the steering arms ill-and l l carry theball portions of the ball joints" l5 and it, whilethesockets therefor are formed at the ends of members. such as M having stems screw threaded in those ends 01: the tubular tie rods l2 and 53. which are connected to the steering arms. The opposite ends of the tie rods lzand .13 are provided respectively, with a cranked extension 25"screw threaded in the end of the tie rod 12. and carrying the ball portion of the'ball joint M, and a socket therefor formed threaded in the end of the tie rod it.

joints I5 and M of the tie rod I2, is asocket', for theball-portionof the ball joint 26 which is car- 'Because the steering gear center line of the vehicle, a construction accord-' ing to the invention has the advantage that the l8 with' its' pitman arm i9 is offset to one side of the longitudinal 40 at the end of a member 26 having a stern screw ball'joints 20 and M'may be similarly offseton I thesame side of the center line, to provide jincreased clearance for the engine or other neces- I sary parts mounted centrally between the wheels opposite sides of the longitudinal center line of the vehicle and may be bent as may be desired to clear what would otherwise be obstructions on the center line of the vehicle. I

It will be appreciated that the screw threaded members 24, and 25, 26, provide for any necessary "adjustment of the length of the tie rods l2 and I3 and that by choosing in suitable combination, the disposition and'the actual and relative lengths of the sections l2, l3 and 25 of the tie rods, the length and position of the steering arms I!) and H in relation to the shorter upper arms 6 and the longer lower arms I, and the angle if any, at which the pivot axes of the arms 6 and 1 are set to the normally vertical longitudinal midplane of the vehicle a steering linkage can be obtained in which the upward and downward deflections of the wheels relatively to the frame cause but little or no movement of the wheels about their steering axes (i. e. their king pin axis or its equivalent); or expressed otherwise the steering will be substantially unaffected by upward and-downward deflections of the wheels relatively to the frame. The'tie rod I2 will turn about the center 2 and will have an effective length equal to the radius of the arc described by the point I5 of the steeringarm as the wheel 4 is deflected upwardly and downwardlyrelatively to the frame; while the tie rod i3 is obviously longer than the tie rod l2, its effective length as compared with the tie rod I2 is reduced to the extent that the center 14, about which it turns with upward and downward deflections of the wheels, itself moves When this is done, one of the tie rods in an arc of a circle about the center 20, thereby compensating for the actual difference in length of the tierods I 2 and I3 and making them of the same eifective length. l v

The pivot axis of the arms 6 and I for each wheel need not be divergent away from the normally vertically longitudinal mid-plane of the vehicle as shown, but may be parallel thereto. The

greater the separation between the virtual axes wheels on opposite sides of a vehicle frame, in-

cluding two tie rods pivotally connected to each other and to the wheels on opposite sides of the vehicle, and a steering gear box on the frame, having a pitman arm pivotally connected to one of the tie rods at a point intermediate of its pivotal connections to one of the wheels and to the other tie rod.

2. "The combination according to claim 1, in which the steering 'gear box including its pitman arm, is offset on one side of the normally vertical longitudinal mid-plane of thevehic1e, said pitman arm being connected to the tie rod of the Wheel on that side of the vehicle.

3. The combination according to claim 1 in which that tie rod to which the pitman arm is I pivotally connected is shorter than the other tie rod. v

4. The combinationaccording to claim 1, in which the tie rod to which the pitman arm is connected includes a part having an adjustable 1 connection with the remainder of the said tie rod, the pitman arm and the other tie rod both being pivotally connected to the said part.

HENRY O. FUCHS. 

